Engineering Chemistry Multiple Choice Questions on “Gaseous Fuels – 1”.
1. Which of the following is a disadvantage of gaseous fuel?
a) Gaseous fuels are very difficult to operate
b) Gaseous fuels are highly inflammable
c) Gaseous fuels cannot be ignited instantly
d) They produce lot of smoke on combustion
Answer: b
Clarification: The particles in gaseous fuels are separated from each other, due to which their combustion becomes very easy. This increases the inflammability of the gaseous fuel. Special care should be taken to avoid fire hazards.
2. Which of the following is a major advantage of gaseous fuel over liquid and solid fuel?
a) Gaseous coal does not form ash
b) Gaseous coal can be manufactured at a central place
c) Oxidising and reducing atmospheres can be easily maintained
d) They are economic than solid and liquid fuels
Answer: a
Clarification: Ash content is present in the fuel itself. Due to the presence of ash content in solid and liquid fuels, its rate of combustion decreases. Also, a lot of smoke is generated due to the presence of ash content.
3. Which of the following is a primary gaseous fuel?
a) Water gas
b) Oil gas
c) Refinery gas
d) Liquefied petroleum gas
Answer: d
Clarification: Primary gaseous fuel are those, which are already present in nature and secondary gaseous fuels are those which are obtained from primary gaseous fuels. Natural gas is also a primary gaseous fuel.
4. Which of the following compound is present in natural gas?
a) Urea
b) Benzoyl peroxide
c) Methane
d) Sulphonic acid
Answer: c
Clarification: Natural gas is mainly composed of methane and small quantities of ethane and other hydrocarbons. Urea consists of nitrogen due to which it is not present in natural gas.
5. Which type of natural gas is called wet natural gas?
a) Containing lower hydrocarbon with more ethane
b) Containing higher hydrocarbon with more ethane
c) Containing lower hydrocarbon with more methane
d) Containing higher hydrocarbon with more methane
Answer: d
Clarification: If higher hydrocarbons are present along with methane, then the natural gas is called “Rich” or “Wet” natural gas. It is also called “Marsh gas” because it majorly contains methane.
6. From which of the following natural gas is majorly obtained?
a) From oil fields
b) From coal fields
c) From seas
d) From sun
Answer: a
Clarification: Most of the natural gas used as fuel is derived from oil fields. However, sometimes, the gas is evaporated from the oil and diffused through rocks, is trapped by impervious dome shaped structure.
7. Which of the following natural gas has the highest ignition temperature?
a) Natural gas obtained from oil fields
b) Natural gas obtained from coal fields
c) Natural gas obtained from rocks
d) Natural gas obtained from sea
Answer: c
Clarification: The natural gas produced from rocks by the diffusion of oil constituents a gas field that may be under high pressure. Due to this high pressure, the flow potential of gas increase, which produces static electricity and increases the ignition temperature which is hazardous for us.
8. How much percentile of propane is present in natural gas?
a) 5.5 %
b) 3.7 %
c) 1.8 %
d) 0.5 %
Answer: b
Clarification: At an average 88.5 % of methane is present in natural gas. 5.5 % of ethane, 3.7 % of propane and 1.8 % of butane are present in natural gas. The higher hydrocarbons are present at about 0.5 %.
9. H2S is not present in natural gas.
a) True
b) False
Answer: b
Clarification: H2S is present in small quantity in natural gas. If it is present in an appreciable amount, then it is called as “Sour” natural gas. At the maximum 15 % of H2S in found in natural gas till now.
10. Which of the following process is used to recover vapours of liquid hydrocarbons in wet natural gas?
a) Evaporation
b) Distillation
c) Cracking
d) Adsorption
Answer: d
Clarification: The vapours of liquid hydrocarbons can be recovered by condensation, absorption in oil and by adsorption on charcoal, silica or alumina gel. The liquid so recovered is called casinghead gasoline.